Composite Semaphore Flag for the Letter W - Whiskey
The Composite Semaphore Flag for Whiskey has a yellow background, because W is the 23rd letter of the alphabet. Reason being, 3 is coded to yellow and the ones digit value of a letter sets the colour. As a reminder yellow is the third colour of the spectrum. Also the stars represent the right-starboard arm of the Semaphore Signaler.